Diary Entries in English

Recent diary entries

To GDAL or not to GDAL

GDAL is an incredible geospatial library and underpins so much of what we do, including our databases (PostGIS).

However, sometimes it might be a bit heavyweight for what we are trying to achieve. Installing it as a base system dependency inevitably installs everything - there are no options.


Install size is especially important when building container images, that we want to be as small as possible for distribution.


PostGIS uses GDAL for most of it’s geospatial processing, including reading and writing various geospatial file formats.

FMTM is starting to use FlatGeobuf format for various purposes (data extracts, storing submissions). It also uses a PostGIS database as part of the software stack.

So today I thought: why not just use GDAL in the database instead of installing into the API server container?

The solution was surprisingly painless!

Database Access

First we need a way to access the database.

FMTM is using FastAPI and SQLAlchemy, so ideally we want to pass through and reuse the database session created when an endpoint is accessed.

To make this standalone, I also added functionality to create a database engine from scratch.


The nitty-gritty SQL


Now I’m sure this is a much more efficient way to write this by nesting SQL SELECTs, but I was too lazy to debug and I find this approach quite readable, albeit slightly less efficient.

Using the code

An example of using in FastAPI:



There is one glaringly obvious limitation of this approach: if reading the FlatGeobuf is implemented in the same way then we lose the benefit of it’s ‘cloud native’ encoding.

Reading requires downloading the entire file, passing to PostGIS, and returning a GeoJSON.

However, that was not the intended purpose of this workaround.

FlatGeobuf is primarily a format meant for browser consumption. With excellent support via the npm package.

So while the backend API can write data to FlatGeobuf without requiring dependencies, the frontend can then read the data if it’s hosted somewhere online (i.e. an S3 bucket).


Apologies for the code screenshots: OSM Diaries does not support code syntax highlighting, nor spaces in code blocks.

Database code

from sqlalchemy.engine import create_engine from sqlalchemy.orm import DeclarativeBase, Session def get_engine(db: Union[str, Session]): """Get engine from existing Session, or connection string. If `db` is a connection string, a new engine is generated. """ if isinstance(db, Session): return db.get_bind() elif isinstance(db, str): return create_engine(db) else: msg = "The `db` variable is not a valid string or Session" log.error(msg) raise ValueError(msg)

SQL code

from geojson import FeatureCollection from sqlalchemy.orm import Session def geojson_to_flatgeobuf(db: Session, geojson: FeatureCollection): """From a given FeatureCollection, return a memory flatgeobuf obj.""" sql = f""" DROP TABLE IF EXISTS public.temp_features CASCADE; CREATE TABLE IF NOT EXISTS public.temp_features( id serial PRIMARY KEY, geom geometry ); WITH data AS (SELECT '{geojson}'::json AS fc) INSERT INTO public.temp_features (geom) SELECT ST_AsText(ST_GeomFromGeoJSON(feat->>'geometry')) AS geom FROM ( SELECT json_array_elements(fc->'features') AS feat FROM data ) AS f; WITH thegeom AS (SELECT * FROM public.temp_features) SELECT ST_AsFlatGeobuf(thegeom.*) FROM thegeom; """ # Run the SQL result = db.execute(text(sql)) # Get a memoryview object, then extract to Bytes flatgeobuf = result.fetchone()[0].tobytes() # Cleanup table db.execute(text("DROP TABLE IF EXISTS public.temp_features CASCADE;")) return flatgeobuf

Usage code:

from sqlalchemy.engine import create_engine from sqlalchemy.orm import DeclarativeBase, Session def get_engine(db: Union[str, Session]): """Get engine from existing Session, or connection string. If `db` is a connection string, a new engine is generated. """ if isinstance(db, Session): return db.get_bind() elif isinstance(db, str): return create_engine(db) else: msg = "The `db` variable is not a valid string or Session" log.error(msg) raise ValueError(msg)

Location: Kampung Padang, Kampung Bharu, Kuala Lumpur, 50400, Malaysia

Activation info:

Activation: Libya Floods 2023

Activation Declared: Sep 14, 2023

Activation Concluded: Nov 9, 2023

Debrief Conducted by: Pete Masters, HOT, Activation Lead

Relevant statistics

Contributor statistics over the lifetime of the activation

Contributor statistics over the lifetime of the activation

Project stats from the Libya Floods activation

Tasking Manager project statistics for the activation

Narrative summary:

In collaboration with OSM Libya and supported by UN Mappers a HOT activation was declared to map areas affected by floods following Storm Daniel, with a specific focus on Dernah due to the collapse of the dams in the city. As the activation unfolded, priority areas were added (areas for which were prioritised by OSM Libya) as projects on the HOT Tasking Manager for urban areas including Bayda, Susah and Al Marj as well as the rural area surrounding Al Marj after (unconfirmed) reports from UNDAC of damage to a third dam. As the priority areas are now well mapped and validated (the last building project is 99% mapped and 97% validated), the Activation is now concluded.

Dernah post-floods on openaerialmap

Dernah post-floods on openaerialmap

During the activation, in addition to the tasking manager mapping, the MapSwipe community completed four projects (see example) as part of a collaborative effort with MapAction to identify all affected settlements (unfortunately, MapAction ceased their activities before this could be concluded). The MapSwipe data was subsequently used to optimise tasking manager projects.

Open aerial imagery was also requested and received through the Maxar Open Data Programme. This imagery was hosted on OpenAerialMap and used by mappers to ensure up-to-date data and also by a UNDAC Dam specialist (introduced to HOT through the MapAction connection) in an attempt to validate reports of damage to the third dam. The analysis of the imagery was used to inform a Joint Environment Unit report on the dams.

Communications could have benefited from a more timely central comms approach in that shares and amplification sometimes lagged the response so the info shared was already out of date. The HOT website was underutilised (the response used social media, community channels and OSM diary as vehicles for mapper mobilisation and partner engagement).

A special mention for validators for this activation as the validation kept pace with the mapping throughout and we saw amazing commitment from the HOT Global Validator Team and OSM Libya in this regard.

The conclusion of the activation is a collaborative decision with OSM Libya. They will continue to lead on mapping to support recovery activities and HOT has supported through the integration of MapSwipe data into their existing tasking manager projects in order to help mappers prioritise their efforts. OSM Libya will also compile a comprehensive report detailing all activities undertaken in the past two months since the activation’s launch in collaboration with HOT to be shared with the broader community and potentially offer insights to other communities facing similar disasters to that experienced by Libya.

Successes, issues and lessons learnt

[SUCCESSES] What went well?

  • Clear coordination between central and hub team (WNA) - HOT internal
  • Collaboration with OSM Libya throughout (launching activation, defining priorities, technical support)
  • UN Mappers collaboration on launch
  • MapSwipe to tasking manager workflow for rural areas
  • Good quality tasking manager projects (right size, constrained to priority features)
  • Great validation progress (core group of validators has been thanked!)
  • Wiki page kept up-to-date and coordination good in disaster mapping channel
  • Maxar responsive through Open Data Program

[ISSUES] What could have gone better?

  • Confusion over Libya responsibility (in a HOT priority region, but not a HOT priority country)
  • Activation ‘could have’ started 2-3 days earlier (UN Mappers feedback)
  • OSM Libya upgrading existing general projects to urgent as a response not ideal (projects too big and unspecific)
  • Neglected HDX update until it was flagged by a partner
  • Discussions with OSM Libya on activation didn’t happen in a publicly accessible forum (live chat) so OEG compliance tricky
  • HOT comms around the activation was sometimes lacking / lagging
  • Need a better process for working with responders. They don’t necessarily use slack or want to.
  • Should we have methodology for requests like consolidated settlement layers?
  • Hard to know to what extent HOT has capacity for technical GIS / data analysis requests.
  • Didn’t make use of the karta view data for Dernah

[SUGGESTIONS] What lessons should influence how we activate in future?

  • Smaller tasking manager projects (less tasks ~700 per project worked well for this activation) that focus on one feature each
  • MapSwipe affected rural areas immediately
  • Tasking manager activation projects should be reviewed asap and support provided for improvements
  • Project creator role to answer queries / do problem solving, especially early on
  • Need to think about how we engage orgs like Digital Egypt (did a lot of damage mapping)
  • Need a clear view / publicly available list of possible service offers for responders
  • We need to think about the recovery and the map - updating to post-event data
  • We don’t have great arabic language capacity in our core community and networks - something to develop?
  • Mechanism to alert or at least ask to local communities if mapping is needed in the case of a natural disaster event, by monitoring in real time natural disasters happening across the globe (UN Mappers)

Follow up:

If you have questions and / or comments related to the activation or this documentation, please contact Pete Masters at HOT

Video showing the easiness of streetcomplete

Link to the original message in

Short video showing the easiness of using @streetcomplete to improve OpenStreetMap and all projects which rely on it e.g. #cyclosm

Link to a Peer2Tube video on

Feel free to spread the video to promote Streetcomplete use!

Posted by jcr83 on 5 December 2023 in English (English). Last updated on 6 December 2023.

Version française


Many paths, tracks and even small streets are missing from OSM. And yet, these paths are often used by Strava users, who upload their traces there. So I thought it would be interesting to use these data to improve OSM.

That’s why I wrote a Python program which, by analyzing Strava data, is able to detect missing paths in OSM, then generate files to create MapRoulette challenges so that each missing path can be added to OSM.

What is Strava?

According to Wikipedia, Strava is a website and mobile application used to record sports activities via GPS. Its members use devices such as a GPS watch or smartphone to record their running activities, and send these to Strava. Currently (2023), there are over 100 million members.

Strava heat maps

On its website, Strava publishes a heat map showing the aggregation of all its users’ tracks.

Example: Strava heatmap example

The more a route is ridden, the brighter its track appears on the heatmap.

In fact, there are several Strava heatmaps, one for each activity (running, cycling, skiing…). We use the running map, which is the most accurate due to the low speed of runners, and which reflects all paths, even those impassable in other activities.

Precautions to take when using Strava

You shouldn’t always blindly trust the tracks on the Strava heat map. Indeed:

  • Tracks may be obsolete, following a major climatic event that destroyed paths (for example, in 2020, storm Alex destroyed many paths in the French Alps).
  • Tracks may correspond to trail runs that have taken off-trail routes or private property.
  • Ski runs and ski lifts may appear on the running map, if users have not indicated that they practice winter sports.

Principle of missing ways detection

The software analyzes the Strava heat map to detect bright trails near which there is no path in the OpenStreetMap database.

The detection threshold can be set according to three criteria:

  • minimum brightness level (from 0 to 255).
  • minimum distance from an OSM path.
  • minimum track size.

The Strava heat map is supplied in the form of 512 x 512 pixel tiles. Each tile is analyzed independently of the others. To avoid detecting the same path twice when it straddles two contiguous tiles, it is possible to analyze only one tile out of four. This means you need to perform four analyses and update the MapRoulette challenge each time.

MapRoulette challenges in progress

Metropolitan France



The source code is available in this Github repository. The installation procedure is described in the file.

How to add a new challenge for another area

If you want to add a new MapRoulette challenge for another area, the principle is as follows:

  • on the OSM-Boundaries site, download the boundaries of the area you’re interested in, choosing the Land only option. You’ll get a file in GeoJSON format.
  • run the program, passing the boundary file as a parameter. For example, for the Principality of Andorra:

python -v -a Andorra.geojson -g Andorra_Missing_Ways.geojson

  • Create a MapRoulette challenge and select the I want to upload a GeoJSON file option to upload the Andorra_Missing_Ways.geojson file.

More information in the file of the Github repository.

Posted by Eden Oluigbo on 5 December 2023 in English (English). Last updated on 6 December 2023.

👋🏼 Hello and welcome to my blog space where I share everything about my journey with Outreachy, HOTOSM and more. Thank you for joining me on this exciting journey! I am very excited to be part of the Outreachy program and If you’re interested in knowing the rest of my story, which I am willing to share it all :), please subscribe to my posts, so you get notified every time I publish a blog on my journey. Just like everything that ever existed, there’s always a beginning. So let’s zoom🔍 out a little bit to where it all began 😊.

image that says "the journey is on"


My name is Eden Oluigbo. I am a full-stack developer, artist and creator living in Abuja, Nigeria. I'm an open-source advocate and love contributing to the improvement of open source software. I started an active contribution to open-source projects in 2022. I joined different communities, made contributions and got PR merges (that excitement of having your PR merged never gets old haha😁).

Why Outreachy?

In the process of my active contribution to open source, I found out about [Outreachy]( on twitter (now X). I did my research and was excited about their commitment to diversity within the open source community, so I applied for the December 2023 cohorts and I got selected for a 3 months internship at Humanitarian OpenStreetMap Team [HOTOSM]( , where I will be making contributions as a "Tech Community Engagement Intern" staring from December 4th, 2023 to March 1st, 2024.

The contribution phase was quite busy, but it got fun as we attained more clarity in my group at HOTOSM. The collaborative spirit was culpable and I cannot overemphasise how amazing and patient my mentor, Petya Kangalova is. If you’re an Outreachy applicant reading my story, and maybe wasn’t accepted for the internship, do not be discouraged. Our stories are different and so is our journey. Continue your journey in open source, improve more on your skills, and apply again. I’ve read stories of people who got accepted on their second application. In the meantime, celebrate with me and keep learning! 🎉 meme about beginning

My Core Values

Core values are important personality traits. In the intricate essence of our lives, core values serves as the foundational layers, binding together the fabric of our characters and defining the essence of who we are. Here are the core values that inspired my journey with Outreachy and HOTOSM.

1. Diversity:

I love and celebrate Diversity. The recognition that each unique expression of our differences contributes to the richness of the whole. In a world adorned with varieties of cultures, perspectives and backgrounds; embracing diversity expands our horizons, fostering an environment where every voice is heard. Outreachy and HOTOSM are vivid homes of diversity😊

2. Curiosity:

Curiosity is the spark that ignites discovery. I was that kid that would open up a toy car, or a TV remote, because I wanted to see what's inside that makes the car move or what makes the remote control the TV. My mom liked that I was curious to learn, but didn't like the part I was destroying things😅. I love to ask questions, I want to know how things work, seeking to understand and venture into the unknown. That's how I learnt the things I know today, and I don't intend to stop. A commitment to curiosity fuels perpetual learning, turning every encounter into an opportunity for growth and broadening our perspectives.

3. Creativity & Excellence:

I have a mantra that guides my output to anything I'm doing, and that is "If it's not good enough for me, then it's not good enough for the next person". So, I commit to delivering my very best, not as a destination, but as a means, which results to a relentless pursuit of high standards. I consider myself VERY creative, and that allows me to bring a brush of originality and innovation, not to reinvent the wheel, but to improve on what already exists.


These core values are my anchors and inspiration for being part of the Outreachy programme (fiscal sponsored by Software Freedom Conservancy). I have no regret in joining Outreachy and more so, I am super excited to be selected to work in an organisation in line with my values and passion for humanity, HOTOSM.

I love it here at [HOTOSM]( ; the community is diverse and inclusive. The staff are super kind and teachable; eager to share what they know and open to learn from you. Work-life balance lives here. My mentor [Petya Kangalova]( ; she's just amazing!💯😎

I look forward to making a positive impact and leaving a good example for the next intern at HOTOSM. For a quick start, I created this guide to contributing to HOTOSM projects. Please click [here]( to watch the video. I encourage you to [join HOTOSM]( and build a career through open-source contribution in a diverse and inclusive community!

Posted by nukeador on 5 December 2023 in English (English). Last updated on 6 December 2023.

This is a cross post from the HOTOSM blog.

As Community Strategist and Research Lead at HOT, I would like to take a closer look with you all at the evolving landscape of OpenStreetMap (OSM) contributors, especially in the context of local knowledge and its crucial role in our mapping efforts.


Our recent study reveals a trend in local knowledge contributions in OpenStreetMap: a small but dedicated number of local mappers, making up just about 3% of contributors who are in the area mapping, is responsible for approximately 75% of the detailed mapping contributions.

This significant finding underscores the vital role of local knowledge and expertise in creating comprehensive and accurate maps, especially in humanitarian and unmapped/under-mapped regions. Despite a general decline in new OSM contributors, the impact of this core group of local mappers remains profound and indispensable for the future of the project.

We would like to engage researchers and mapping communities to unveil what are the implications of these numbers and the opportunities to use them to better support mappers.

The Spark of Inquiry: Simon Poole’s Analysis

Our journey began with Simon Poole’s important observation: a 20% drop in new OSM contributors. This sparked intense discussions within our team and motivated us to investigate further, particularly focusing on regions where HOT is actively involved.

Our findings validated a consistent decline in the number of contributors in most of the 33 countries analyzed over the past five years. However, intriguingly, the volume of mapped elements, like buildings and roads, has been on the rise. This disconnect between contributor numbers and mapping activity led us to delve deeper into the nature of these contributions with deeper analysis.

Why Understanding Local Contributions in OSM Matters

Grasping the dynamics of local contributions to OpenStreetMap is more than just number crunching – it’s about ensuring that maps reflect the lived realities of communities worldwide.

In regions facing humanitarian crises or high poverty levels, local knowledge in mapping becomes invaluable. Accurate maps created with local insights can significantly aid in delivering effective aid and developing sustainable solutions. Our focus on this aspect underscores the need to nurture and support local mapping communities.

Pioneering Methodologies: Towards a Better Understanding

One of our main challenges was to distinguish between local and remote contributions. With the support of Caleb Fagunloye, our Data Analytics and Insights Intern, we developed a pilot methodology focusing on data contributions indicative of ground surveying or field mapping. This innovative approach, though not without its limitations, allowed us to isolate mapping contributions that are likely to come from local knowledge.

We took Rebecca Firth’s illustrative humanitarian mapping framework and isolated the contributions in levels 2-4, essentially excluding edits to the map that could be made using satellite imagery.

We then looked at the users (usernames) who made these changes to try and understand who was adding local knowledge to OSM in these countries in 2022.

Key Insights: The Role of Local Champions

Average: Percentage of contributors and changes they made

  • Our analysis showed that a small proportion of contributors (~3%) were responsible for the majority of local knowledge changes (~75%). This highlights the significant impact of a few highly active local OSM champions.
  • However, this also points to a potential vulnerability in terms of sustainability and depth of community engagement. What happens if these key contributors reduce their activity?

Here you can see a table with the full data for some countries we analyzed, note how just a few contributors are responsible for most of the changes:

Country Total changes to elements (2022) # contributors who made these changes % (#) of contributors responsible for 50% of the changes % (#) of contributors responsible for 75% of the changes % (#) of contributors responsible for 95% of the changes
Nepal 50239 713 0,4% (3) 1,8% (13) 12% (86)
Senegal 2338 172 1,7% (3) 7% (12) 43,6% (75)
Kenya 7415 313 1% (3) 2,6% (8) 28% (87)
Mexico 38556 1078 0,5% (5) 2,6% (28) 21,1% (227)

Some of the numbers here were very surprising. For example, three people in Kenya, Senegal and Nepal were responsible for 50% of all the local knowledge changes to OSM in those countries in 2022.

Forward Path: Expanding Research and Engagement

  • We welcome improvements to the methodology! The more solid it is, the better our understanding of the OSM community landscape will be.
  • Our early research has opened avenues for more comprehensive analysis, especially focusing on the long tail contributions of casual mappers and social science / anthropological explorations
  • We think we still need to understand this analysis in other locations and analyze the evolution and trends over time.
  • HOT will keep the peer to peer support to individuals and communities to implement collective and collaborative actions, improve resources and skills and enable tech to empower and facilitate these local knowledge edits.
  • We have also published a notebook with the code to replicate this user extraction and analysis, for the countries and years of your interest. It shouldn’t take more than 15-20 minutes to get some results.


The pilot methodology above is far from perfect. For example, we know that it is possible to add ‘local knowledge’ data to the map remotely (MapRoulette campaigns and imports are two examples).

The tag list used for the analysis also has some known flaws, such as road names being excluded even though they are likely to indicate local knowledge.

It is also really important to say that a Kenyan or Mexican mapper who only does mapping using satellite imagery is still a very valid member of that community of contributors! Although we did this research because we believe in the value of local knowledge in the map, it is not a judgment on other mapping methods!

Also note that the analysis includes people who are mapping on their employee capacity for a corporation/organization, who tend to contribute in high volumes. Taking this into account for a follow-up study and finding ways to exclude them from the numbers, might provide a more realistic picture of paid and not-paid contributions.

Open questions from SoTM EU presentation

This analysis was presented by Pete Masters during the recent State of the Map Europe 2023 and some interesting discussion followed.

  • The situation was familiar for members of more mature OSM communities. Those with now very active local knowledge contributors recognised that, in the past, a small number of very committed mappers did the majority of the field mapping and surveying.
  • Could these ‘core mappers’ end up being gatekeepers and discourage newer mappers from developing their OSM contribution?
  • Where should we allocate resources in supporting local knowledge contributors - new people to OSM, mappers who have shown inclination to add local knowledge or the core mapper group? Do efforts tend to focus on new mappers to the detriment of other groups?
  • Why do mappers do what they do? One hypothesis is that people contributing high quantities of local knowledge data do so because they have a purpose for that data. Is this true? If not, what drives core mappers?
  • How does this analysis look spatially? Does a core mapper in Nepal mean that their home town is very detailed with towns further away increasingly lacking in local knowledge?
  • How does 2022 compare with 2023 or 2021? This is a snapshot, not a trend at the moment.

A Call to Action

Our journey doesn’t end here. We see this as a stepping stone towards a more extensive, nuanced analysis of OSM contributions. We invite community leaders, social scientists, and OSM enthusiasts to join us in this endeavor. Your insights and expertise are invaluable in shaping the future of open mapping.

Posted by joyceeemaeee on 4 December 2023 in English (English).

Another year, another Pista ng Mapa 2023 in Tacloban City!

Hosted by UP Visayas Tacloban YouthMappers, it’s a gathering celebrating open mapping, data, and an unforgettable journey. I am grateful to the organizing team for the scholarship grant and the chance to present. Thank you, UP Tacloban Youthmappers, for the warm welcome and for keeping our surroundings pristine.

The conference was a three-day journey packed with eye-opening lightning talks. From Leanne Caye D. Obispo’s “Data: A Story to Tell” to Sir Denrazir Atara’s spatial analysis of tree species, each session was a revelation. Erika Del Rosario Pauline Jen Madrona’s drone training and Oriel Jay Ibañez’s insights on community development through drone imaging were inspiring. Sir Ben Hur Pintor’s discourse on data management and Ms. Dinnah Feye Andal’s introduction to Mapillary were eye-openers. And oh, the endless field trip—such a blast! where I can say I shall return to Tacloban

Meeting old friends, making new ones on social nights, connecting with mentors again like Sir Mikko Tamura, Ms. Feye Andal, Leigh Lunas, Sir Ben Hur, and Sir Aimon, and connecting with the local YouthMappers chapters were a highlight! This was my 2nd Pista ng Mapa 2023, a great adventure with a small team with Dora (Me), yet the knowledge gained, networks built, and friendships forged were beyond measure. Here’s to hoping next year brings even more from our chapter.

I look forward to creating new memories and deepening my mapping passion at the next Pista ng Mapa (also SotM, manifesting!). Huge thanks to everyone who made this event an unforgettable experience!

Location: Barangay 6-A, Tacloban, Eastern Visayas, 6500, Philippines

Thank you


Asante sana

Your participation in 2023 GIS Day Conference was hugely appreciated

"Geospatial technology stands as a cornerstone for fostering a robust digital economy in Tanzania,serving as a catalyst for achieving sustainable development that will secure a prosperous future for forthcoming"

Dr. Moses Nkundwe Mwasaga, DG ICT Commission

Throughout the conference, we witnessed over 200+ participants gathered at the Tanzania Commission for Science and Technology (COSTECH) in Dar es Salaam to exchange knowledge and participate in dialogue on utilising geospatial technology for sustainable development in Tanzania.

The conference brought together geospatial enthusiasts, leaders, and practitioners across industries, the private and public sector, academia, and civil society organizations to promote changes that can be made at the community, producer, and government levels for sustainable development.

Engaged participants included:

  • 20+government officials from Tanzania
  • 90+donor partners, CSO reps, and experts in the geospatial field
  • 30+academicians
  • 60+secondary students


Session 1: Welcoming and History of GIS in Tanzania

Aim: Setting the context and history of GIS technology and its evolution in Tanzania.

Summary: Chief Edwin Mugerezi provided insights into the historical journey of GIS in Tanzania, acknowledging GIS pioneers and sponsors. This section aimed to contextualize the significance of GIS Day in the Tanzanian context.

Session 2: Opening Panel: Status of Geospatial Technology

Aim: Assessing the current state of geospatial technology, the policy landscape, challenges, and opportunities

Summary: Dr. Moses Nkundwe, Dr. Zakaria Ngereja, Ibrahim Mambo, and Antidius Kawamala led discussions on the comprehensive analysis of geospatial technology in Tanzania, emphasizing policy aspects and exploring the challenges and opportunities in the field.

Session 3: Revolutionizing Agriculture with Geospatial Technology

Aim: Exploring how geospatial technology contributes to the agricultural revolution and food security.

Summary:Dr. George Mulamula, Dr. Beatrice Tarimo, Erick Tamba, and Dr.Rose Funja discussed the transformative role of geospatial technology in agriculture, focusing on its implications for food security and innovative approaches to farming practices.

Session 4: GIS in Climate Risk Assessment and Disaster Management

Aim: Analyzing the use of GIS in climate risk assessment and disaster management strategies.

Summary: Abdullasat Ghaamid and Studio delved into the application of GIS in climate risk assessment, disaster management, and the critical role of geospatial data in mitigating environmental risks.

Session 5: Geospatial Technology in Tourism and Blue Economy

Aim: Highlighting the significance of geospatial technology in tourism development and the blue economy

Summary: Dr. Atupelye Komba, Simon Machera, Samira, and Steven Kangaile discussed geospatial technology's impact on tourism development and its role in fostering sustainable practices in the blue economy.

Session 6: GIS Water Project: State of the art

Aim: Showcasing the power of geospatial technology in water sector

Summary: Xavier Torret and Antidius Kawamala discussed the power of geospatial tools and solutions from B GEO and how the technology is revolutionizing the water sector.

Session 7: GIS User stories and use cases

Aim: Showcasing innovative GIS projects and how best the technology is being utilized.

Summary: Different projects from TANAPA (Tanzania National Parks Authority), GST (Geological Society Tanzania), NBS (National Bureau of Statistics), Tukutech (Geophysical Survey), and many more were presented on how they have been utilizing GIS in their day-to-day activities.

Session 8: Exhibitions

Aim: Showcasing innovative GIS projects in wider aspect and how best is the technology being utilized.

Summary: Different exhibitors from ESRI East Africa, Youth Mappers, GeoTE, Alpha Infinity Company Limited, AM3, and Info bridge actively engaged with conference participants, showcasing how they have been utilizing GIS in their day-to-day activities.

Session 9: Our Cities Mapathon

Aim: To create and produce basemaps in cities across Eastern and Southern Africa.

Summary: Conference participants came together and joined hands in creating free geospatial data that will help in producing basemaps in cities across Eastern and Southern Africa. This mapathon focused on mapping Langata Nairobi through the Cities Spatial People Award.

Conference Materials

You can now access the photos.

Session notes and videos will soon be available with other GIS Day Tanzania 2023 Conference Materials HERE.


You can read more about ROOTGISand GIS Day through their website.


GIS Day 2024 will be hosted by ROOTGIS and other partners to be confirmed , if you are interested in taking part next year send as an email through or visit our offices.


Front Desk - or 255769806836

Location: University Residential Houses, Kijitonyama, Kinondoni Municipal, Dar es Salaam, Coastal Zone, 25195, Tanzania
Posted by rtnf on 2 December 2023 in English (English).

Today, I received an email regarding the Foundation Board election. It’s finally time to vote. So, I read all the board candidates’ manifestos and Q&A session answers before finally deciding on whom to vote for.

While reading those materials, I came across several interesting quotes along the way. Take a look :

My long-term vision for OpenStreetMap is it becoming the default map because it has eclipsed its competitors in accuracy, completeness, actuality and detail.

The ideal state of OpenStreetMap is trivially a state where everyone knows that the project exists. The threshold to contribute shall be so low that everyone can record or update any map feature they consider notable.

First of all, I would like to thank all DWG members for the enormous amount of work they have to do to ensure that our work is not destroyed. If elected to the board, I will try to ensure that part of the OSMF funds are allocated to solutions that facilitate the work of DWG colleagues as well as to support them in recruiting new volunteers.

The recent cases of vandalism in Ukraine and Israel have undermined trust in our data; some data consumers have stopped updating their maps there. Investing in advanced tools to aid the Data Working Group is imperative for enhancing prevention, detection, and reversion of vandalism.

The board should consult the community on what to do for large anonymous donations if we have that luxury problem in the future. I am strongly against strings attached to any donations. The only ones we have ever accepted was the promise that we would earmark the donated funds for the fundraised purpose.

Our greatest strength is our community of editors, and as long as we are united, the project will not be at risk.

We shall start to attract the next generation. The existing generation of mappers have been intrinsically motivated by the absence of useable map data before OpenStreetMap came to frution. Now, good map data is a commodity, and we need to retell the story to remind people that there is hard and ongoing work behind the data.

Strengthening local chapters is vital, not just for diversity but to encourage local initiatives that improve quality.

We should explore support for temporary data like festivals or roadworks and maybe even real-time data integration. This could significantly enhance the utility and relevance of our maps.

2024 promises to be an exciting year with the launch of our new vector tiles. These will be open-schema, minutely updated, and designed for easy remixing with personal or open datasets.

A few years back, I successfully led a crowdfunding effort to raise £975 to purchase scans of the 1970s / 1980s 1:50k topographic map series of South West Africa / Namibia from a commercial map archive. It was a great success and I put them online:

Recently I have been speaking to the archive again about purchasing similar map series for other African countries. The map series vary per country from the 1960s to 1990s. Many were created with support from the United Kingdom’s former Directorate of Overseas Surveys (DOS).

The 1991 1:50k Topographic series of Swaziland (now Eswatini) published by the Swaziland’s Surveyor General is available. It is made up of 31 sheets in total. The scans are supplied clipped and unclipped. Total price is US$ 400 for the scans.

It would be fantastic to get these maps online. Would you be willing to support this purchase?

Link: Worldcat reference for the 1991 Swaziland map series.

Example of the join between 4 cropped sheets: Example of 4 cropped sheets joining

Location: Extension 3, Mbabane, Inkhundla Mbabane, Hhohho Region, H100, Eswatini

Hello, i’m maplemoths. This is my first diary entry, and i decided it’d be fun to discuss OSM topics occasionally here.

What have i been mapping recently?

I’ve been doing tons more mapping recently, because it’s pretty fun. It’s nice to just listen to music/twitch stream vods, and just map. Here’s what i’ve mapped recently.


Most recently, i’ve been mapping in Hawai’i. A large amount of my edits actually are in Hawai’i in general, because i used to live there. Specifically, i’ve mostly been editing in the city i lived in, Hilo. When i first started mapping in i believe September of 2022, Hilo’s map quality wasn’t super good. Lots of missing landuse or POIs, lots of stuff that was all offset from eachother, the polygons were really messy, etc. But, i feel like there’s been tons of progress! I’ve been working on making things better, and there’s been some progress from others. There’s been more landuse, i cleaned up lots of the messy/incorrect polygons, and i’ve also micromapped the zoo right outside of the city, but i’ve also done some other stuff in the area.

Plains, Georgia

A lot of times, i map an area because something interesting has happened there, or that it’s significant for an interesting reason. Examples include me mapping Oleona in Pennsylvania because the area was the site of a small failed Norwegian colony, and yes, Plains, Georgia. It’s a small little town right in the south of Georgia that’s famous for being the hometown of US president Jimmy Carter, so i decided to map it! I mostly did landuse and cleanup, and it was quite fun! If you’re wondering, i did not map the town because of Rosalynn Carter’s death, i started the project a month earlier but only finished it after.

What do i plan to do next?

This section is for stuff i want to get to, and maybe i can get some help on if you want!

More Hawai’i

I still have much to do in Hawai’i. My main focuses currently are on landuse, POIs, some micromapping, and a lot of polygon cleanup. The interior of the Big Island has much work that i want to help with, mostly natural stuff. The Hawai’i Volcanoes national park also has some work i’d like to do, mostly natural landuse and trails.

Pueblo, Colorado

I live in Pueblo, so it’s natural i want to do mapping here. I’ve done plenty already, but i have some goals. Pueblo does not have many homes mapped, which i would like to do even though it’ll take a long time. There’s also some landuse that should be done. Once imagery updates, i’d like to micromap some of the new school buildings that have opened recently but aren’t displayed on imagery yet. These schools are Chavez Huerta K-12 Preparatory Academy’s recent new school buildings, Centennial High School’s new building, and East High School’s new building.

Monterey, California

When i went there, i loved it. So, i want to do more mapping of the city! I’ve already done some landuse and micromapping of the college, but i’d like to do more.

More outside of the USA

Most of my edits are in the USA, but i’d like to do more worldwide edits. If anyone knows some countries that are undermapped, i’d like to see what they are!


That’s the end of the entry, for now. is there anything that catches your attention about my post, or any questions or help? I’d love to have some! I will post more occasionally. Goodbye, have a great day! :3

well, i’ve mapped on both locations..


but if you want to learn something about climate change and its consequences, you better chose to travel to vunidogoloa.

Posted by DW2515 on 1 December 2023 in English (English).

Dear OpenStreetMap Community, As we celebrate the vibrant spirit of OpenStreetMap (OSM) and the incredible progress it has made over the years in the upcoming annual meeting, I am excited to express my interest and enthusiasm in becoming a potential board member for the OpenStreetMap Foundation.

While I may not boast thousands and thousands of edits on the OSM platform, I have dedicated my efforts to advocacy and education, recognizing the which I think play a crucial role these aspects play in fostering a thriving OSM community. My journey with OpenStreetMap has been one of constant learning, teaching, engagement, and a commitment to making OSM accessible and valuable to people users around the world.

From when I made my first OSM edit in Nepal during a HOTOSM & Maptime Miami Mapathon. (Maptime is a global volunteer meetup group that teaches beginners and experienced folks alike about mapping, geography, OSM and more.) Since then I have volunteered to teach others about OSM in a few ways, such as through Maptime meetups, where I served as the leader of Maptime chapters in Miami and Boston, and to teaching the basics of geography and OSM to Young African Leaders Initiative (YALI) fellows about how they can use and apply geography and OSM in their communities, to leading Maptime chapters in Miami and Boston (as I moved around).

For the past three years, I have had the privilege of serving on the OpenStreetMap US (OSMUS) Board, where my I focused on collaboration and commitment to community values and collaboration has been paramount. In my role as a member of the Code of Conduct Committee, I actively contributed to the drafting of the official Code of Conduct for OSMUS, ensuring a welcoming and inclusive environment for all members. Additionally, I played was a volunteer organizer a crucial role in of the organizing Mapping USA and State of the Map US Conferences, facilitating spaces for knowledge exchange and community building. Throughout my tenure on the board, I’ve made it a priority to actively listen to the needs of the OpenStreetMap community, striving to bridge gaps and promote a vibrant and supportive atmosphere within OSMUS.

Advocacy has been at the forefront of my contributions, as I firmly believe that awareness and understanding are key components to the sustained success of any open-source project. I’ve also worked with OSM as part of my career in transportation planning, where through my work, I have strived to explore shed light on the potential of OpenStreetMap in more unconventional areas, such as its capability to map curbs / kerbs – “seize the curb” as I like to call it.

One of my articles, titled “Potential for OpenStreetMap to Seize the Curb”, explores the innovative ways OSM can be used utilized to map the curb effectively. This not only showcases the versatility of OSM but also underscores its relevance in addressing real-world challenges such as mobility, transit and accessibility. Additionally, I had the honor of presenting my insights at the 2018 and 2021 State of the Map US conferences , where I delved more into the intricate details of curb mapping using OpenStreetMap.

My passion for education extends beyond individual projects. I believe in empowering OSM users with the knowledge and skills they need to contribute meaningfully to the map. As a board member, I envision creating and supporting initiatives that foster learning, inclusivity, and collaboration within the OpenStreetMap community, and to welcome and support more chapters around the world.

I understand that my candidacy might differ from others in terms of edit counts, but I think editing is only one of many ways people can contribute to the OSM project. I firmly believe that a holistic approach is vital for the overall health and sustainability of any community. I believe my focus on advocacy and education complements the technical expertise present in our diverse community, with the goal of contributing to a more well-rounded and robust OSM ecosystem.

I am excited about the opportunity to bring my unique perspective, energy, and dedication to the OpenStreetMap Foundation Board. Together, let’s continue building a map that truly represents the world we live in.

Thank you for considering my nomination. - Daniela (Dani)

Posted by spwoodcock on 29 November 2023 in English (English). Last updated on 6 December 2023.

See pt1 of this series here.

First Release

We have been running various versions of FMTM for some time now, but released our first official version not long ago: v0.1.0.


See the excellent release notes written by Susmina Manandhar, product manager for FMTM, for further details of features, bug fixes, and improvements.

Just to reiterate what a wonderful team of devs we have working on the project: @varun2948, @nrjadkry, @Sujanadh, @NSUWAL.

Special thanks for @JoltCode, an volunteer, who helped to modernise our frontend build tools. And to @robsavoye for his work on osm-fieldwork and osm-rawdata that underpin FMTM, plus guidance from the start.

Try it out!

I have been working to ease the installation process for organisations that need to run FMTM.

You can run a version of FMTM yourself with two commands!

curl -L -o


You will be prompted with a command line interface

Although HOT will endeavour to run a ‘global’ instance of FMTM, in a similar vein to Tasking Manager currently, my main goal is that FMTM is so simple to deploy, that a workflow such as this can be envisioned:

  1. Requirement for field mapping arises.
  2. Organisation spins up an instance of FMTM.
  3. Project manager creates a project, divides tasks.
  4. Team goes out to map the features.
  5. Data is validated, conflated with existing OSM data, and exported / uploaded.
  6. FMTM instance is shut down.

Technical aside / mad idea section:

To run FMTM, currently all you need is a server and a domain name.

In the future, this could be streamlined even further with a technology such as Headscale, creating a virtual private mesh network for mappers to connect to.

HOT could potentially run the Headscale control plane, so all project managers would need to do is run FMTM on their laptop/pc, configure the VPN for their users, then connect phones to the VPN (using an easy mobile app) for mapping!

Mobile First

We realised during various test with end users, that the UI was far from ideal to operate via mobile phone.

Significant updates have been made to the UI design, adopting a mobile-first approach to ease field usage for mappers on the ground.


We now also support map geolocation and orientation.

The project creation workflow has also undergone significant upgrades.


MBTile Output

Often mapping must be undertaken in areas with limited connectivity.

To still use a basemap to locate yourself, the MBTile format is useful. MBTiles can be generated directly in FMTM for download and use within ODK Collect.


Note: we are working with the developers of ODK Collect to make the process of loading MBTiles into the app a more seamless process.

Improved Deployment Process

As mentioned, HOT plans to maintain a series of FMTM servers for usage by the public.

In our newly improved deployment process, this is as follows:

The purpose behind having a staging server open to the public is to gather feedback and run public tests of new features.

Those wishing to use FMTM for a critical project should use the production server.

However, if you wish to have the latest features on FMTM as quickly as possible (the development pace is quite fast), but are willing to encounter the occasional bug, then feel free to use the staging server (and please provide feedback!).

The staging version should be updated every two weeks.

The stable version should be released every month.

Get Involved

Contributing to FMTM with code, documentation, or ideas would be very welcome!

Software developers, technical documentation writers, software testers, or anyone with a general interest - feel free to get in contact.

Future Posts

This was an update on some of the latest features of FMTM and future plans.

There is much that I could not cover, so please check Github for the latest updates!

I plan to make future posts about developments, technical deep dives, and usage of FMTM’s features.

See you next time.

Location: Prima Tanjung Business Centre, Tanjung Tokong, North-East, George Town, Penang, Malaysia

Tl;dr: this is a somewhat technical post, so if you are interested primarily in finding alternatives to OSM Analytics, please scroll down to the last section. This post is being created in conjunction with a Community Forum topic as well, so any feedback or comments should be directed there.


What is OSM Analytics?

For the past 8 years HOT has been supporting the hosting and maintenance of OSM Analytics. This service was built by Martin Raifer, hired by HOT with support by the Knight Foundation. It was originally developed to help people analyze and visualize OSM data it multiple ways:

  • Density and distribution of OSM features such as buildings, roads, hospitals, amenities, places and waterways from aggregated low zoom levels (world scale) all the way to individual features;
  • Total count of OSM features over different areas, including any admin boundary, user defined area of interest or custom GeoJSON;
  • Recency of edits displayed in a timeline graph, allowing users to select specific time periods and visualize the corresponding edits on the map
  • Visual distribution of features mapped by OSM contributors with different levels of experience, allowing interactive selection of experience levels and automatically displaying relevant features
  • Gap analysis, showing areas of estimated completeness with regards to buildings mapped;
  • Change over time, allowing users to compare density, distribution and total count of OSM features in any area at any zoom levels, between any two years from 2007 to now
  • Top OSM contributors and top distinct tags for any user defined areas, allowing interactive filtering through the timeline slider selector

Technical functionality

On the backend, OSMA relies on OSM QA Tiles and a data “cruncher” hosted by the HeiGIT lab at Heidelberg University. Until 2018 the QA tiles were processed daily and hosted by MapBox, then they were migrated over to HOT infrastructure. The OSM Analytics API continues to be hosted by HeiGIT (documented here). Additional charting functionalities for using and visualizing OSM Analytics data in other web applications is documented here. An example of these functionalities in action can be seen in the Open Cities Africa project website, where charts and statistics are sources interactively from OSMA. Any update to the OSMA data will automatically reflect in each web page.


Not much has changed with this tool over the years. This year OSM Analytics received about 2200 unique visits, seeing a gradual decline since we started tracking in 2019. HOT did not invest in updating dependencies, fixing bugs (Martin has generously continued to support in this effort without recognition), or optimizing performance of the OSM QA Tiles processor since the initial development and release. When HOT took over hosting and running the QA Tiles processor, we reduced the frequency of updates for QA Tiles to weekly, as this was the majority of the cost to the service overall.

Alternative analysis tools

At HOT, our Tech & Data team’s current focus is on facilitating mapping activity with our tools and enabling everyone in our focus regions to map, with a mission to map areas home to 1 billion people. Our technology stack aims at uniting people in our focus countries around mapping: We are improving the Tasking Manager, focusing on improving the quality of data being added to the map and making mapping more effective by leveraging ethical, open source AI modeling. We are prioritizing where humans are most in the loop through coordinated mobile data collection of higher-level data by adding more detailed and accurate tag information. In the meantime, we realize that leaves a gap for some users of OSM Analytics.

Since 2022, we are partnering with HeiGIT to really understand the contributions to the map and analyze the data being created by humanitarian mappers. The ohsome dashboard provides statistics on map data currentness and saturation, but it was not expressly built to replace OSM Analytics. HeiGIT has also produced the ohsome History Explorer (ohsome Hex) to explore edits on OSM.

HOT has also invested heavily in building a data processing engine called Underpass, which is just now entering the prototyping stage where data can be analyzed at scale. Other recent tools can provide similar statistics as well, such as Kontur’s From HOT’s perspective the APIs available from HeiGIT and Underpass will have a greater scope of analysis, higher accuracy, and flexible use-case to provide as a service to the OSM community.

We are seeking your feedback: Alongside this diary post we have also created a topic on the Community Forum where we can engage in a fruitful discussion about the future of OSM Analytics, alternatives, and currently missing functionality.

I have been working on placing the boundary in the correct location, or at least as “correct” as is technically possible. Before I started this, the boundary was mostly mapped using (as best as I can tell) data from the Canadian “Canvec” and “Geobase” datasets along the St. Croix River, and the NAD83 coordinates published by the International Boundary Commission in Passamaquoddy Bay. This was roughly correct in most cases, but some in some places the boundary is/was completely on the wrong side of the river. Essentially, we have been using the edge of the Canadian hydrography dataset as the national border.

The actual border

The actual position of the border is defined by the Treaty of 1908, as modified by the treaties of 1920 and 1925. The text of these treaties can be found on the website of the International Boundary Commission. The general message from actually looking at them is that the determinations and demarcations of the IBC are “definitive”… the boundary is where the IBC says it is, in their official publications and on their official maps.

These publications can be found in scanned form on HathiTrust. All but Special Reports 8 and 9 predate the adoption of the North American Datum of 1983… this means that the official position of most of the boundary is actually defined in either the pre-1927 United States Standard Datum, or the North American Datum of 1927.

While the IBC does publish a shapefile of the boundary (in NAD83) and a “coordinate listing” for each section in both NAD27 and NAD83, these files are of limited use. They are explicitly stated to be not official, and I have found obvious typos that would locate the border miles out of position. Also, the given NAD83 coordinates are unhelpful since they do not state which “realization” of NAD83 they are in. OSM is capable of storing coordinates to a degree of precision at which this makes a difference.

Obtaining correct coordinates

Because of these issues, the only method of accurately locating the border is to use the original coordinates as published in the original datum, bring them forward to NAD83, and then convert them to WGS84. When doing so, it’s important to have a understanding of how these systems are actually related in order to end up with coordinates that are as correct as possible. This is because, while the transformations between the USSD, NAD27, and NAD83 are static, those between NAD83 and WGS84 are not. While there have been multiple “realizations” of NAD83, the definition of the system has not changed. Instead, the revisions of NAD83 have been to correct network inaccuracies as the precision of measurement has improved. This means that the most current realization, NAD83(2011), should be used to give the most accurate result. The reference epoch for this is 2010.0.

NAD83 vs WGS84

When NAD83 was initially published in 1986, was defined on the the GRS 80 spheroid. This has not changed.. NAD 83 is a “fixed, geometric ellipsoid that doesn’t change it’s location as more accurate information becomes available.” This is not true for WGS84. NAD83 was initially, in 1984, the same as both WGS84 and the “International Terrestrial Reference Frame”, but both have been redefined multiple times since. This is done for the ITRF by the International Earth Rotation and Reference Systems Service, to result in “zero net rotation” while also improving the reference spheroid. The US Department of Defense then occasionally adjusts WGS84 to match the ITRF. Every time this is done, the WGS84 Prime Meridian moves, to match the ITRF at a specific point in time. This was last done in early 2021.

The center of the NAD83 “Earth” is now several meters away from the center of the center of the WGS84 “Earth,” and the offset between the two systems varies over time. This means that any rigorous transformation between the two requires knowing the epoch of the coordinates being used.

The current realization of the ITRF is “ITRF2020”, and the current realization of WGS84 is “WGS84 (G2139)”. These systems are defined to be coincident at the reference epoch of 2015.0. This is the system in which a GPS unit gives coordinates, and thus what is effectively used by OSM.

Putting it together

The process, then, begins with obtaining the NAD27 coordinates, and converting them to NAD83 (2011). I am using the NGS Coordinate Conversion and Transformation Tool ( to do this. This places the coordinates at the reference epoch of 2010.0. I am then using NOAA’s “Vertical Datum Transformation” tool ( to convert the coordinates to ITRF2020 @ 2015.0, with the elevation set to zero (the NAVD 88 zero point is mean sea level).

For portions of the boundary located on land (I’m not there yet) only the second step will be needed, since the NGS publishes well-determined locations for the boundary monuments in NAD83, as well as elevations.

Using this process, the main source of error in the calculated positions should be due to the unknown elevations (the convergence factor). I intend to post tables of the original and converted coordinates to the wiki, for future reference if the nodes are moved, or if I have made an error.

Hopefully, this will be a useful read for anyone looking to convert published geodetic positions for use on the map.

I am happy to announce that after a long time we, the OpenStreetMap Carto maintainers, have prepared a new release of the OpenStreetMap Carto stylesheet (the default stylesheet on the OSM website). Once changes are deployed on it will take couple of days before all tiles show the new rendering.

Here are some details on the visible changes this release brings to the style.

Changing color of leisure=pitch to be more distinct and less similar to the water color

The color of leisure=pitch had a long time ago be adjusted to be less strong. But this change had resulted in pitches often being hard to distinguish in the map from water areas and other green areas even though pitches are a highly distinctive feature that is typically small in size - which calls for a strong color in principle. This modification changes the color of leisure=pitch to be more distinct and recognizable again and at the same time to harmonically integrate with the other colors used.

leisure=pitch color change

thanks to Justin Gruca for implementing this change.

Fixing color of ref label for railway=subway_entrance

The color of labels for subway entrances (railway=subway_entrance) was not exactly the same as otherwise used for transportation symbols and this change fixed that inconsistency.

railway=subway_entrance color change

thanks to kaneap for this change.

Fixes for highway=mini_roundabout rendering on various road types

There were several errors leading to inconsistent styling in the rendering of highway=mini_roundabout on some road types, which were fixed now with this change. This also adds support for highway=mini_roundabout, highway=turning_circle and highway=turning_loop on highway=trunk roads.

highway=mini_roundabout styling fixes

thanks to Thomas Pétillon for implementing this change.

Fixing merge error in previous change of rendering natural=bay/natural=strait

previous changes to the labeling of natural=bay/natural=strait - which meant to unify display of bays/straits mapped with nodes, linear ways and polygons - were accidentally modified during merging and this change implements the labeling strategy that was originally meant to be implemented (together with some code cleanup).

bay/strait rendering fix

Removing point symbol rendering for golf=hole

golf=hole is by convention tagged on linear ways describing the route from the tee to the pin. It has previously been rendered on nodes as a synonym for golf=pin, but it is not used this meaning so this change removed that rendering to avoid counterproductive mapper feedback and to simplify the code.

golf=hole rendering change

thanks to Benjamin Schultz Larsen for implementing this.

Restoring rendering for railway=platform + covered=yes

So far railway=platform with addon tag covered=yes was not rendered - just like railway=platform + location=underground and railway=platform + tunnel=yes. The first of these is now shown just like plain railway=platform - while the others are still hidden to avoid confusing mixing of underground features with above-the-ground elements. In addition, display of railway=platform is now consistent between linear way and polygon features.

railway=platform + covered=yes change

thanks to map-per for this change.

Adding rendering of roller_coaster=track

roller_coaster=track is now rendered on linear ways with a distinct line signature. This is done in a separate layer outside the road rendering system and supports bridge and tunnel tagging with a distinct styling.

roller_coaster=track rendering

thanks to tjur0 for implementing this.

Adding rendering of landuse=flowerbed

The tag landuse=flowerbed is used by mappers to map areas were flowers are planted for decorative purposes. The tag started to increase strongly in use in 2020, is well defined and used with very good consistency. And it fits well into our existing scheme of green landcover rendering - so we had wanted to support this in OSM-Carto for some time. A suitable design was now developed with regular patterns of relatively subtle contrast - simple dots at z15 and z16 (on a grass color background) and small flower symbols at z17+.

landuse=flowerbed rendering

thanks to Mattijs Leon for implementing this change. Thanks also to Hungerburg, daganzdaanda and Jean-Marc Liotier for previous work on this issue.

Other changes

This release also includes various other, non-visible changes. For a full list of commits, see…v5.8.0


The OSM-Carto maintainers thank all contributors. Particular thanks go to the new contributors:

  • Benjamin Schultz Larsen,
  • dch0ph,
  • kaneap,
  • Matija Nalis,
  • Mattijs Leon,
  • Nicolas Peugnet,
  • tjur0

As always, we welcome any bug reports at

We also invite anyone interested in contributing to the project. New contributors can find a list of issues that are suitable for less experienced style developers. We also have a list of bigger challenges of the project that need work.